DENVER — Sexual assault reports at the three US military academies rose 64 percent in the 2009-10 academic year, but many more victims probably didn’t come forward, the Defense Department said yesterday.
A total of 41 sexual assaults involving students were reported to authorities at West Point, the Naval Academy, and the Air Force Academy in 2009-10, the department said in its annual report on sexual harassment and violence.
In the previous academic year, 25 were reported.
Officials point to a survey of students at the three academies taken last spring as well as statistics from the civilian population as indicators that the reported sexual assaults represent less than 10 percent of all types of unwanted sexual contact, ranging from fondling to intercourse.
It was not immediately clear what percentage of the respondents had reported behavior that would qualify as a sexual assault.
Sexual offenses are “one of the nation’s most underreported crimes,’’ said Kaye Whitley, director of the Defense Department’s Sexual Assault Prevention and Response program, which issued the report.
Improved reporting of sexual assaults is one of the department’s key goals, Whitley said.
The report calls the increase in assault reports “concerning,’’ but Whitley said she was encouraged that more people came forward. She said the increase in reports doesn’t necessarily mean that more people were assaulted.
The Air Force Academy, in Colorado Springs, Colo., had the largest increase in reported sexual assaults, from eight in 2008-09 to 20 the next year, a jump of 150 percent.
West Point — officially named the US Military Academy, in West Point, N.Y. — reported 10 assaults in 2009-10, an increase of one. The Naval Academy, in Annapolis, Md., reported 11 assaults in 2009-10, an increase of three.
Air Force Colonel Reni Renner said the eight reported at the Air Force Academy in 2008-09 may have been unusually low. In 2006-07, 19 were reported, and in 2007-08, it was 24.
Renner said she doesn’t know the reason for the low number in 2008-09, but some at the academy have speculated that a sexual assault case that was dismissed instead of going to trial may have discouraged some victims from reporting.
Renner said she also doesn’t know why the Air Force Academy has more reports than the other two schools but said it could stem from the confidence students have in the academy’s sexual assault response coordinator.
The survey showed 47 percent of female respondents and the same percentage of males at the Air Force Academy regarded the coordinator as a valuable resource to “a large extent.’’
At the Naval Academy and West Point, the percentages for the same answer ranged from 14 percent to 19 percent for female and male respondents.
The report outlines each academy’s efforts to improve sexual assault prevention training and reporting and to improve the “climate of victim confidence’’ to encourage victims to report attacks.
Whitley said the survey of students indicated the message of the training is getting through, with more than half the respondents indicating they thought the training was effective in reducing assaults.
Statistical verification that the programs are reducing assaults is elusive, Whitley said.
“Prevention is the most difficult program to measure because you never know how many sexual assaults your program prevented,’’ she said.